Stacked interlocking terminal blocks



May 2, 1967 A. R. NORDEN 3,317,886

STACKED INTERLOCKING TERMINAL BLOCKS Filed June 30, 1964 2 Sheets-Sheet 1 FIG. 2

FIG. 7

y 2, 1957 A. R. NORDEN 3,317,886

STACKED INTEHLOCKING TERMINAL BLOCKS Filed June 30, 1964 2 Sheets-SheetZ United States Patent 3,317,886 STACKED INTERLOCKING TERMINAL BLOCKS Alexander R. Norden, 350 Central Park W., New York, NY. 10025 Filed June 30, 1964, Ser. No. 379,162 11 Claims. (Cl. 339-198) The present invention relates to electrical terminal blocks, particularly to modular terminal blocks that are assembled to provide various numbers of connections, as may be required.

Terminal blocks are used on electrical circuit units for providing convenient separable connection between the wires of a piece of electrical unit and external wires to be connected to the unit. A terminal block includes a body of insulation and one or more conductors having terminals, each conductor having a terminal such as a screw at each end for making circuit connections. Unitary terminal blocks have been produced having various numbers of connectors. From one piece of equipment to another, the number of such circuit connectors varies. It has been found uneconomical to attempt to manufacture special terminal blocks having the particular circuit connectors for an infinite variety of electrical units, taking into account the various numbers of circuits involved, the various current ratings required, and so forth. For this reason, a widespread practice has developed of providing individual terminal blocks of modular design that can be assembled in a row, the row being long enough to provide the necessary number of connectors. Improved forms of terminal blocks of this type are disclosed in my copending application, Ser. No. 271,160, filed Apr. 8, 1963, now Patent No. 3,253,251 dated May 24, 1966.

A broad feature of the present invention resides in the provision of novel modular terminal blocks that are adapted for assembly not only in rows, but are also for assembly with one row of terminal blocks on top of another.

Modular terminal blocks are frequently of a form to be received on a mounting rail, and for this purpose the bottom of such modular terminal blocks have formations that interlock with the mounting rail. A feature of the present invention resides in the provision of mounting formations at the bottom of each terminal block and, at the top of each terminal block, there are complementary interlocking formations so that one terminal block can be mounted on a mounting rail, and another terminal block may be assembled on top of the first one, the bottom formations of the second terminal block interlocking with the interlock formations at the top of the lower terminal block. A related feature of the invention is in the utilization of the barriers between each circuit connector of a block and its neighbors on that terminal block, for the further purpose of complementarily receiving the formations at the bottom of another terminal block when the latter terminal block is assembled on top of the first one.

A still further feature of the invention resides in the provision of specially located fasteners such as screws, in addition to or in substitution for the interlock formations between any given terminal block and another terminal block that is to be secured on top of the first one.

Where a large number of circuit connections are to be made and a simple row of terminal blocks is provided by assembling a number of terminal blocks on a rail, the wires connected to the terminal blocks are disposed sideby-side. Space limitations sometimes limit the maximum length that is permissible. Pursuant to a broad feature of the invention, multiple rows of modular terminal blocks can be assembled one row on another for increasing the number of circuit connections without increasing the over- 3,317,886 Patented May 2, 1967 all length of the terminal block assembly. In an assembly of the novel terminal blocks, according to a further novel feature, the circuit connectors of any one block are laterally displaced from the circuit connectors of another terminal block that is above or below the first one in the assembly. By virtue of this feature, the terminal connections of the connectors of the lowermost row of terminal blocks are readily accessible (as with a screwdriver) without interference from wires that extend to the circuit connectors of the terminal blocks in a row immediately above the first-mentioned terminal blocks.

Accordingly, an object of the present invention resides in the provision of modular terminal blocks that are adapted for rigid interlocking assembly, in which the terminal blocks are arranged not only in a row but also where multiple rows are stacked securely; wherein modular terminal blocks are adapted for mutual assembly one on another by means of interlocking formations and without resort to additional fastening means; wherein multiple modular terminal blocks are provided with fasteners such as screws that may be used either in addition to or in substitution for interlocking formations; wherein the terminal blocks are adapted to be assembled in multiple securely stacked rows; wherein the terminal portions of each circuit connector in any row of terminal blocks is readily accessible without obstruction by the terminal wires extending to the circuit connectors of the terminal blocks directly above the first-mentioned terminal blocks; and wherein further novel features are included, as will be apparent in the detailed description of the illustrative embodiment that follows, this embodiment being shown in the annexed drawings.

The presently preferred embodiment of the invention in its various aspects is shown in the accompanying drawings which are described in detail below, and in that detailed description further objects, novel features and advantages will be apparent. It will be recognized that while this is the presently preferred embodiment of the invention, it is susceptible of varied application and modification so as to utilize some of the novel features without the others. In the accompanying drawings:

FIGURE 1 is the plan view of a three-circuit terminal block incorporating novel features of the invention;

FIGURE 2 is a cross-section of the terminal block of FIG. 1, along the line 2-2, together with a mounting rail that is also shown in cross-section;

FIGURE 3 is another cross-section of the terminal block of FIG. 1 along the line 3-3 of FIG. 1;

FIGURE 4 is a bottom view of the terminal block as shown in FIG. 1;

FIGURES 5 and 6 are fragmentary enlarged perspective views, partly in cross-section, of the top and bottom, respectively, of the terminal block of FIGS. 1-4, inclusive;

FIGURE 7 is an end view of two terminal blocks of FIGS. 1-6 in stacked assembly on a mounting rail;

FIGURE 8 is a longitudinal cross-section of the stacked terminal blocks in FIG. 7; and

FIGURE 9 is a lateral view of a number of terminal blocks in accordance with FIGS. 1-8, assembled in three stacked rows, the bottom row being mounted on a mounting rail.

Referring now to the drawings, the terminal blocks are seen to include a block 10 of molded insulation, the material being relatively stiff but capable of yielding to a limited degree for utilizing the interlock formations described in detail below. A preferred material for molded block 10 is nylon. The terminal block shown has three circuit connectors generally designated 12 (FIG. 1) each including a strip of metal 14, such as copper, and a screwand-nut assembly 16, 18 at each end of strip 14. The ends of strip 14 are angled downward as shown, the ends of the strip abutting portions 20 of the molded block 10. Pockets or cavities 22 are provided in block 10 for receiving nuts 18 and for accommodating the ends of screws 16. Barriers 24a are interposed between each circuit connector 14 and its neighbor, and barriers 24b extend across the ends of the molded block 10. It may be considered that the molded block 10 includes a body portion 26 below each strip 14 and that the barriers 24a and 24b extend integrally from those body portions 26, the barriers flanking the circuit connectors 12. Extending inward from the lateral surfaces of barriers 24a and 24b are a number of nibs 28 that overhang strips 14 and prevent them from being lifted out of place. Strip 14 is assembled into the position illustrated by being forced past nibs 28, this mode of assembly being feasible where the material of block 10 is capable of limited yielding. If rigid insulation were used, then other means would be used for retaining circuit connectors 12 in assembly to molded block 10.

As seen in FIGS. 2 and 6, molded block 10 includes feet 30 that extend downward, these feet being generally in alignment with the respective barriers 24. These feet have portions 30a (FIG. 6) that are only slightly less than the space between confronting barriers 24a and 24b, and portions 30b that are half the width of portions 30a.

In FIG. 2, block 10 is shown assembled to a mounting rail 32 in the form of a channel having a pair of laterally spaced upstanding walls whose upper edges are turned in at a slant angle. Molded block 10 includes a pair of downward-extending interlock formations 34 that complement rail 32, for holding the terminal blocks in place. Between feet 30 and formations 34 are webs 36 which strengthen formations 34 (FIGS. 2 and 4) these webs being received in corresponding notches in rail 32, thereby resisting endwise shift of the terminal blocks along rail 32. This construction is described in greater detail in my patent mentioned above.

Barriers 24a and 24b have upper interlock formations 38 that are complementary to and interlock with the lower formations 34 of another like terminal block. Thus, as is best shown in FIG. 5, each formation 34 includes a relatively long, gently sloping outer surface 34a that serves as a cam when the molded block is being forced down onto rail 34 in assembling the block to the rail. The same outer cam surface is an aid in assembling a given block to the top of another block (FIG. 7). Further, formations 34 include inward surfaces 34b that slant more sharply, for retention by the in-turned upper edges of rail 32, as previously mentioned. The upper interlock formations in barriers 24a and 24b include complementary portions, including portions 38a complementary to lower interlock portions 34a, and portions 38b complementary to lower interlock portions 34b when multiple blocks are assembled, as is best shown in FIG. 7. Portions 34a and 34b define a raised portion 340 that interferes with port-ion 38b of a lower block 10a (FIG. 7) when block 10b is being forced down onto lower block 10a. When this direct-downward mode of assembly is utilized, molded blocks 10 are made of a molding material such as nylon having stiffness yet having a limited yielding quality. Obstruction 34c of one block 10b is received in a recess 380 of the interlock formation of the companion lower block 10a. (FIGS. 2, 5, 6 and 7.) Similarly, portion 38!) (FIGS. 2, and 6) represents an obstruction on block a that is received in a recess 340 when the interlock formations of blocks 10a and 10b (FIG. 7) are fully assembled.

As best seen in FIGS. 7 and 8, the feet 30 have wide portions 30a that are received between a pair of confronting barriers 24a or between confronting barriers 24a and 24b of another assembled block, these feet serving to prevent endwise shift of one block in relation to the other. Feet 30 have narrow portions 30b (FIG. 8) which are aligned with end barriers 24b, and occupy very nearly half the space between a pair of confronting barriers. The thickness of barriers 24b is nearly half that of barriers 24a. When a pair of modular blocks 10 are assembled end-to-end, the composite thickness of the abutting barriers 24b of those two blocks is equal to that of a barrier 24a; and similarly the depending feet 30b of a pair of end-to-end assembled blocks equal the width of one Wide foot portion 30a, so as to be received between a confronting pair of barriers 24a and 24b, or between a pair of barriers 24a.

As best seen in FIGURE 8, a pair of end walls 24b, 24b of two abutting blocks represent a combined thickness equal to a single barrier 24a; and correspondingly a pair of foot portions 30b, 30b of a pair of abutting blocks add in combination to the width of a single foot portion 30a which occupies the entire space between confronting walls 24a and 24b of the lower block 10a. This arrangement locks a stacked pair of blocks against lengthwise shift of one in relation to the other.

Each block has a number of holes 40 for a screw that may be inserted, and each barrier 24a has a corresponding passage 42 of smaller diameter, that is to receive a screw. When two blocks are assembled, as illustrated in FIGURE 8, a screw 44 extends through pierced extrusion 14a of connector strip 14 and through the upper block into a passage in the wall 24a of the lower block. The extrusion 14a of the connector strip provides conductive metal for the current along the strip past the screw-hole, and the interlock of the extrusion in the complemental counterbore at the top of each hole 40 holds the connector in place despite pull on wires held by screws 16. The use of screws 44 is desirable but not essential when the complementary interlock formations 34 and 38 are used, since these interlock formations provide a very large measure of resistance against up-and-down separation of a companion pair of assembled blocks and the feet 30a and 30b which are received between confronting barriers 24 provide a complete safeguard against relative longitudinal shift of one block relative to another in an assembly.

As illustrated in FIGURE 9, a number of blocks can be assembled in three stacked rows. Each block has connectors for three separate circuits, the form of block illustrated in FIGURES 1-8. There are two different relative positions of one block on another. Thus, in FIGURE 8, the end wall 2% of upper block 10b is received between an end wall 24b and the confronting barrier 24a of the lower block 10a. This is the configuration of the lowermost row of blocks 10a and the second row of blocks 10b in FIG. 9. However, it is equally possible to dispose a pair of end barriers 24b of blocks 10c in the top row between a pair of barriers 24a of blocks 10b in the middle row.

It will be observed in FIGURE 9 that the various circuit connectors represented by the screws 16 of one row are laterally offset relative to the screws of the row immediately above it. This is valuable in any compact assembly of terminal blocks because it makes it possible to gain access to any given terminal screw 16 for Wiring and for disconnection in spite of the fact that, at that particular time, wires may already have been secured to the row of screws 16 in the row of terminal blocks immediately above the one being worked on. In the novel stacked assembly of modular terminal blocks, the offset relationship of the terminals of each block in relation to the terminals in the block above it is a further advantageous feature. A screwdriver S (FIG. 7) engaging a terminal screw clears the barrier 24a or 24b of the block above the one being worked on.

The foregoing illustrative embodiment of the invention includes a number of new and useful features and is presently preferred, but a latitude of variation and varied application of such features will be evident to those skilled in the art and therefore the invention should be broadly construed in accordance with its full spirit and scope.

What is claimed is:

1. A modular terminal block for assembly to others like it, including a block of insulation having a series of mutually spaced-apart normally vertical laterally aligned barrier portions, normally horizontal body portions integral with and extending between each barrier 'portion and the next of the series, said barrier portions extending upward from said body portions, and a plurality of circuit connectors extending across said body portions respectively between each of said barrier portions and the next, said body portions having downward-facing interlock formations adapted for locking engagement with a mounting rail, and the parts of said upward extending barrier portions having interlock formations complementary to said downward-facing interlock formations of said body portions, whereby a plurality of such terminal blocks may be stacked in mutually interlocked assembly, with the downward-facing interlock formations of an upper block in interlocking fit with the upward facing interlock formations of the barrier portions of another block.

2. An assembly of modular terminal blocks, each terminal block including a unitary block of insulation having plural body portions, a corresponding number of elongated circuit connectors extending across said body portions and supported by said body. portion, respectively, said block of insulation having a series of elongated insulating barriers flanking said connectors and extending integrally from said body portions, the assembly including a pair of terminal blocks one of which is disposed on the other with at least one barrier of one block of the pair disposed opposite to one said connector and the corresponding body portion of the other block of the pair, and means uniting at least one said barrier of one of said pair of terminal blocks to said corresponding body portion of the other of said pair of terminal blocks for securing said pair of terminal blocks together in staggered relation.

3. An assembly of modular terminal blocks in accordance with claim 2, wherein said uniting means comprises a metal screw having a head bearing on said one connector and extending through said corresponding body portion and said screw having a threaded portion securely received in said one barrier.

4. A terminal block assembly, including a mounting rail, a first row of terminal blocks on said rail and a second row of terminal blocks on said first row of terminal blocks, each of said terminal blocks including a block of insulation, a plurality of generally parallel circuit connectors across said insulation block, the latter having integral barriers of insulation flanking said circuit connectors, the block of insulation having integral downwardly exposed interlock formations and the barriers having integral upwardly exposed formations, the downwardly exposed interlock formations of the first row of terminal blocks being in interlocking engagement with the mounting rail, and the barrier interlock formations of the first row of terminal blocks being in interlocking engagement with the downwardly exposed interlock formations of the second row of terminal blocks.

5. An assembly of modular terminal blocks, each said terminal block including a unitary block of insulation having a plurality of body portions, and each said terminal block including a plurality of elongated circuit connectors extending across and overlying said body portions, a series of elongated barriers flanking said elongated connectors and extending integrally from said body portions, said assembly of terminal blocks including a pair of terminal blocks assembled one on the other with the elongated circuit connectors thereof extending generally parallel to each other, at least one connector of one of said pair of terminal blocks being aligned with one of the barriers of the other of said pair of terminal blocks, and a metal fastener extending from the body portion underlying said one connector of said one block into said one aligned barrier of the other block of said pair for securing the blocks together, the circuit connectors of one of said pair of terminal blocks offset from the circuit connectors of the other of said pair of terminal blocks.

6. An assembly of modular terminal blocks, each said terminal block including a unitary block for insulation having a plurality of body portions, and each said terminal block including a plurality of elongated circuit connectors extending across said body portions, a series of elongated barriers flanking said elongated connectors and extending integrally from said body portions, said assembly of terminal blocks including a pair of terminal blocks assembled one on the other with the elongated circuit connectors thereof extending generally parallel to each other and having terminals at opposite sides of the assembly, the series of circuit connectors of each terminal block of the pair being offset and thus prominently out of rectangular alignment with the circuit connectors of the other terminal block of the pair, at least one barrier of a first block of the pair being disposed opposite to a connector and one body portion of the second block of the pair, and said one barrier of said first block of the pair and said one body portion of the second block of the pair having interlock formations securing said pair of terminal blocks together.

7. An assembly of modular terminal blocks in accordance with claim 6, further including an integral depending orienting element on each said unitary block of insulation aligned with a barrier thereof, the orienting element of said second block extending into the space between a successive pair of barriers of said first block and extending from one of said pair of barriers to the other, thereby to fix the aforesaid offset relationship between the blocks.

8. A terminal block assembly including a mounting rail and modular terminal blocks assembled in plural superposed rows and including a bottom row on said rail and at least one more row on said bottom row, each said terminal block including at least one transversely extending circuit connector having terminals accessible at opposite sides of the terminal block, and a block of electrical insulation supporting said connector, the bottom of each block having an interlock formation shaped so that it establishes interlocking engagement with the rail, and the top of each block having an interlock formation complementary to the bottom interlock formation for establish ing interlocking engagement with the bottom interlock formation of another like block, each block including an orienting formation cooperating with another block assembled thereto so that the connectors in each row of modular terminal blocks in the assembly are in laterally offset positions relative to the connectors in the modular blocks of the adjacent row in the assembly.

9. An assembly of modular terminal blocks, including first and second blocks of like construction, each terminal block including a body of molded insulation, at least one transverse connector carried thereby, barriers projecting upward integrally from said body of insulation and said barriers flanking said connector, the bottom of the body portion under one transverse connector and the top of each said barrier having complemental interlock formations holding the terminal blocks in stacked staggered assembly, and a metal fastener extending from said one transverse connector and through said body portion thereunder and securely received in the barrier interlocked with the last-mentioned body portion.

10. An assembly of like terminal blocks comprising a first and a second terminal block, each including a body of molded insulation and each having a body portion flanked by upstanding integral barriers, and a connector extending across said body portion, a barrier of said first terminal block being opposite the connector of said second terminal block, and a fastener extending from said connector of said second terminal block and through the body portion below said connector and into said opposite barrier of said first terminal block.

11. In combination, a plurality of like modular terminal blocks disposed in a row including regularly spaced exposed terminal fasteners, and at least one additional like modulator terminal block disposed on said row of terminal blocks, each of said like modular terminal blocks including an insulating body supporting at least one of said terminal fasteners and including integral insulating barriers separating each said terminal fastener from its neighbor, the top and bottom of each modular terminal block including complementary integral interlocking formations resisting both mutual separation and lateral shift of said one modular terminal block stacked on said row of terminal blocks, said insulating body being of relatively stiff molded material susceptible of limited yielding during forced assembly of the interlock formations of a pair of stacked blocks, said interlock formations including coacting surfaces at least one of which has a small slant angle to the direction of forced assembly for forcible deflection during the assembly operation.

References Cited by the Examiner UNITED STATES PATENTS 2,766,436 10/1956 Luebking 339-198 FOREIGN PATENTS 69,235 5/1858 France. 762,505 11/1956 Great Britain.

EDWARD C. ALLEN, Primary Examiner.

ALFRED S. TRASK, Examiner. 

2. AN ASSEMBLY OF MODULAR TERMINAL BLOCKS, EACH TERMINAL BLOCK INCLUDING A UNITARY BLOCK OF INSULATION HAVING PLURAL BODY PORTIONS, A CORRESPONDING NUMBER OF ELONGATED CIRCUIT CONNECTORS EXTENDING ACROSS SAID BODY PORTIONS AND SUPPORTED BY SAID BODY PORTION, RESPECTIVELY, SAID BLOCK OF INSULATION HAVING A SERIES OF ELONGATED INSULATING BARRIERS FLANKING SAID CONNECTORS AND EXTENDING INTEGRALLY FROM SAID BODY PORTIONS, THE ASSEMBLY INCLUDING A PAIR OF TERMINAL BLOCKS ONE OF WHICH IS DISPOSED ON THE OTHER WITH AT LEAST ONE BARRIER OF ONE BLOCK OF THE PAIR DISPOSED OPPOSITE TO ONE SAID CONNECTOR AND THE CORRESPONDING BODY PORTION OF THE OTHER BLOCK OF THE PAIR, AND MEANS UNITING AT LEAST ONE SAID BARRIER OF ONE OF SAID PAIR OF TERMINAL BLOCKS TO SAID CORRESPONDING BODY PORTION OF THE OTHER OF SAID PAIR OF TERMINAL BLOCKS FOR SECURING SAID PAIR OF TERMINAL BLOCKS TOGETHER IN STAGGERED RELATION. 